Hockey skates need to meet several criteria to perform at a high level. A hockey skate, for example, must support acceleration forces, cornering forces, and stopping forces. The modern sport of hockey, featuring ever-increasing athleticism of players, demands even more from a hockey skate.
Traditional hockey skates generally include three main components: a boot, a blade-holder (or “holder”), and a steel blade. The boot receives the wearer's foot and is typically made of one or more lightweight materials. The holder is typically a plastic frame including pedestals that connect the boot to the steel blade. The pedestals of the holder are attached to a sole plate of the boot. Traditional holders are generally designed to substantially reduce or eliminate flex in the skate and to fix the blade to the boot such that minimal blade deflection occurs.
Holders are typically connected to the boot via several metal rivets (for example, 14 metal rivets) or similar fasteners. Metal rivets, however, are relatively heavy and do not rigidly fix the holder to the skate boot. Rather, despite the numerous rivets used, energy losses typically result from relative movement that occurs between the boot and the holder. Manufacturing inconsistencies, such as varying rivet-hole locations, can cause improper alignment between the holder and the boot. Further, clearance typically occurs between the outer diameter of the rivet and the inner diameter of the holes in the holder, and the rivets tend to stretch or elongate the holes in the boot and holder during use. Thus, despite the many fasteners used to fix the holder to the boot, numerous variables exist that can negatively affect the energy transfer between the boot and the holder.
Modern hockey players generally desire relatively light and stiff skates. A lighter skate is easier to maneuver, while a stiffer skate transmits leg motion to the skate more efficiently. While these features are generally preferred, certain skaters may prefer different performance properties from their skates.
An effective and efficient skate provides efficient energy transfer during acceleration, cornering, and stopping. During forward acceleration, increased pressure is applied to the front portion of the blade as the skater applies downforce on the balls of the feet, much like a runner. In order to achieve efficient energy transfer to the ice, resulting in maximum blade contact with the ice, the skate or blade needs to deflect or bend. A skate that is capable of twisting allows the rear portion of the skate to rotate toward the lateral or medial side, which allows the blade to contact the ice in this area. If there is no torsional deflection, the blade will partially contact the ice in the front area where the downward force is concentrated, resulting in reduced power transfer.
During cornering, the skater's leg angle changes and the cornering action places a high rotational force on the skate. To efficiently accommodate this change in force, the skate requires a relatively high rotational stiffness. A skate is also subjected to quick directional changes, often initiated by ankle movement. This movement generally distributes force to the interface between the boot and the holder. A traditional skate with an attached holder, however, allows some relative movement between the boot and the holder such that some energy is not transferred to the blade.
During stopping, the skater applies the blade at a cross angle to the direction of travel while leaning inward to place the edge of the blade on the ice to stop momentum. This action places a higher rotational force on the skate than cornering. As with cornering, any relative movement between the boot and holder will reduce the transfer of energy, and thus the stopping force.